1. Field of the Invention
The present invention relates generally to analysis systems for determining the presence and concentrations of hazardous, carcinogenic, etc., chemicals in ground water. In particular, the invention relates to an automated system for operation on site to automatically and independently assay concentrations of analytes of interest, and to communicate analysis data to agencies concerned with health and safety.
2. The Prior Art
Analysis of ground water for analytes of interest has become progressively more important because of concern regarding soil and ground water contamination by industrial chemicals and the like, and by nuclear waste.
The prior art comprises a wide assortment of liquid sampling systems and devices. These fall into three general categories:
(a) devices lowered into a liquid to collect a sample;
(b) devices lowered into a liquid and which pump the liquid to the surface for analysis; and
(c) devices lowered into the liquid and which embody self-contained means for analysis of the liquid and the transmitting of analysis data to a processing station.
Among the prior art patents relative to such liquid sampling devices are the following: U.S. Pat. No. 5,293,934 to Burge et al, U.S. Pat. No. 5,033,551 to C. Grantom, and U.S. Pat. No. 5,708,220 to R. Burge.
Liquid sampling devices of the prior art involve certain disadvantages and shortcomings, which it is the purpose of the present invention to overcome.
Devices which obtain samples by lowering a device into the liquid to be sampled, withdrawing the sample from the liquid, and retrieving and collecting samples, involve time-consumption, tedious processes and expense. A primary disadvantage is that contamination of the sample analyzing means within a submersible sampling device necessarily restricts the accuracy of sample analyses which may be performed, expose the instrumentation to risk of damage, unnecessarily increase the cost and complexity of sampling devices, and preclude utilizing such instrumentation for other purposes, as in laboratories.
Devices lifting a column of water equal in height to the distance from the submerged sample collection device to the surface require very high pump outlet pressure, particularly when a sampling device is a substantial distance below ground surface, such as 1,000 ft. or much more.
There has existed substantial and increasing need for an improved water sampling system and method which provides a complete automatic procedure from sampling through analysis, and under computer program control from sampling to disposal of waste samples and communicating the analysis results automatically to provide an assay for use by appropriate agencies.